Buggy code:
private IPath [ ] inclusionPatterns ; private char [ ] [ ] fullInclusionPatternChars ; private IPath [ ] exclusionPatterns ; private char [ ] [ ] fullExclusionPatternChars ; private static final char [ ] [ ] UNINIT_PATTERNS = new char [ ] [ ] { "Non-initialized<seq2seq4repair_space>yet" . toCharArray ( ) } ; private boolean combineAccessRules ; private String rootID ; private AccessRuleSet accessRuleSet ; static class UnknownXmlElements { String [ ] attributes ; ArrayList children ; } public static final IPath [ ] INCLUDE_ALL = new IPath [ ] { } ; public static final IPath [ ] EXCLUDE_NONE = new IPath [ ] { } ; public static final IClasspathAttribute [ ] NO_EXTRA_ATTRIBUTES = new IClasspathAttribute [ ] { } ; public static final IAccessRule [ ] NO_ACCESS_RULES = new IAccessRule [ ] { } ; public IPath sourceAttachmentPath ; public IPath sourceAttachmentRootPath ; public IPath specificOutputLocation ; public static final int K_OUTPUT = 10 ; public boolean isExported ; IClasspathAttribute [ ] extraAttributes ; public ClasspathEntry ( int contentKind , int entryKind , IPath path , IPath [ ] inclusionPatterns , IPath [ ] exclusionPatterns , IPath sourceAttachmentPath , IPath sourceAttachmentRootPath , IPath specificOutputLocation , boolean isExported , IAccessRule [ ] accessRules , boolean combineAccessRules , IClasspathAttribute [ ] extraAttributes ) { } public boolean combineAccessRules ( ) { } public ClasspathEntry combineWith ( ClasspathEntry referringEntry ) { } private IAccessRule [ ] combine ( IAccessRule [ ] referringRules , IAccessRule [ ] rules , boolean combine ) { } static IClasspathAttribute [ ] decodeExtraAttributes ( NodeList attributes ) { } static IAccessRule [ ] decodeAccessRules ( NodeList list ) { } private static IPath [ ] decodePatterns ( NamedNodeMap nodeMap , String tag ) { } private static void decodeUnknownNode ( Node node , StringBuffer buffer , IJavaProject project ) { } private static void decodeUnknownNode ( Node node , XMLWriter xmlWriter , boolean insertNewLine ) { } public char [ ] [ ] fullExclusionPatternChars ( ) { } public char [ ] [ ] fullInclusionPatternChars ( ) { } public void elementEncode ( XMLWriter writer , IPath projectPath , boolean indent , boolean newLine , Map unknownElements ) { } void encodeExtraAttributes ( XMLWriter writer , boolean indent , boolean newLine ) { } void encodeAccessRules ( XMLWriter writer , boolean indent , boolean newLine ) { } private void encodeAccessRule ( AccessRule accessRule , XMLWriter writer , boolean indent , boolean newLine ) { } private void encodeUnknownChildren ( XMLWriter writer , boolean indent , boolean newLine , ArrayList unknownChildren ) { } public static IClasspathEntry elementDecode ( Element element , IJavaProject project , Map unknownElements ) { } public static NodeList getChildAttributes ( String childName , NodeList children , boolean [ ] foundChildren ) { } private static String removeAttribute ( String nodeName , NamedNodeMap nodeMap ) { } private static Node removeNode ( String nodeName , NamedNodeMap nodeMap ) { } private static void encodePatterns ( IPath [ ] patterns , String tag , Map parameters ) { } public boolean equals ( Object object ) { } private static boolean equalAttributes ( IClasspathAttribute [ ] firstAttributes , IClasspathAttribute [ ] secondAttributes ) { } private static boolean equalPatterns ( IPath [ ] firstPatterns , IPath [ ] secondPatterns ) { } public IAccessRule [ ] getAccessRules ( ) { } public AccessRuleSet getAccessRuleSet ( ) { } public int getContentKind ( ) { } public int getEntryKind ( ) { } public IPath [ ] getExclusionPatterns ( ) { } public IClasspathAttribute [ ] getExtraAttributes ( ) { } private String [ ] getMessageTemplates ( ) { } public IPath [ ] getInclusionPatterns ( ) { } public IPath getOutputLocation ( ) { } public IPath getPath ( ) { } public IPath getSourceAttachmentPath ( ) { } public IPath getSourceAttachmentRootPath ( ) { } public int hashCode ( ) { } public boolean isExported ( ) { } public boolean isOptional ( ) { } static int kindFromString ( String kindStr ) { } static String kindToString ( int kind ) { } public static IAccessRule [ ] getAccessRules ( IPath [ ] accessibleFiles , IPath [ ] nonAccessibleFiles ) { } public String toString ( ) { StringBuffer buffer = new StringBuffer ( ) ; <START_BUG> buffer . append ( getPath ( ) . toString ( ) ) ; <END_BUG> buffer . append ( '[' ) ; switch ( getEntryKind ( ) ) { case IClasspathEntry . CPE_LIBRARY : buffer . append ( "CPE_LIBRARY" ) ; break ; case IClasspathEntry . CPE_PROJECT : buffer . append ( "CPE_PROJECT" ) ; break ; case IClasspathEntry . CPE_SOURCE : buffer . append ( "CPE_SOURCE" ) ; break ; case IClasspathEntry . CPE_VARIABLE : buffer . append ( "CPE_VARIABLE" ) ; break ; case IClasspathEntry . CPE_CONTAINER : buffer . append ( "CPE_CONTAINER" ) ; break ; } buffer . append ( "][" ) ; switch ( getContentKind ( ) ) { case IPackageFragmentRoot . K_BINARY : buffer . append ( "K_BINARY" ) ; break ; case IPackageFragmentRoot . K_SOURCE : buffer . append ( "K_SOURCE" ) ; break ; case ClasspathEntry . K_OUTPUT : buffer . append ( "K_OUTPUT" ) ; break ; } buffer . append ( ']' ) ; if ( ( getSourceAttachmentPath ( ) ) != null ) { buffer . append ( "[sourcePath:" ) ; buffer . append ( getSourceAttachmentPath ( ) ) ; buffer . append ( ']' ) ; } if ( ( getSourceAttachmentRootPath ( ) ) != null ) { buffer . append ( "[rootPath:" ) ; buffer . append ( getSourceAttachmentRootPath ( ) ) ; buffer . append ( ']' ) ; } buffer . append ( "[isExported:" ) ; buffer . append ( this . isExported ) ; buffer . append ( ']' ) ; IPath [ ] patterns = this . inclusionPatterns ; int length ;

Fix:
buffer . append ( String . valueOf ( getPath ( ) ) ) ;